Retractors and specula are of the more common implements known to the surgical arts and are employed to hold open or enlarge a body cavity, incision, wound, or the like, so as to enable the physician to examine the interior of the cavity and to facilitate the insertion and manipulation of surgical implements therein. Conventional retractors are characterized by having a blade portion formed with a shallow, concave curvature and a handle affixed to the blade portion and generally disposed at a right angle thereto. Specula are characterized by a pair of thin duck bill-like blades, the lower blade being generally formed integrally with a handle and the upper blade being pivotally movable with respect to the fixed lower blade, the pivot point being located adjacent the handle.
The conventional blade and handle arrangement has been found to be disadvantageous as the handle interferes with the insertion of other surgical implements into the cavity, and this is especially true in the instances where the retractor is employed for obstetrical or gynecological purposes, as great care must be taken when manipulating the retractor to avoid contact of the handle with the inner thighs which are easily contused.
In order to adequately illuminate the internal portions of the cavity under examination, it has often been necessary to provide a light source external of the instrument which often either failed to provide sufficient illumination or interfered with the examining physician's ability to obtain a clear, unobstructed view of the cavity interior, as such external light sources were located at the rear of the instrument.
Thus, it is desirable to provide a light source integral with the retractor or speculum to overcome the problems associated with an external light source. One such means is disclosed in U.S. Pat. No. 3,324,850, which, inter alia, provides a light source mounted in the interior portion of the lower blade. This arrangement has, however, proved unsatisfactory. As it is often necessary to remove samples of tissue from the body cavity for laboratory analysis, the lower blade of the speculum is used to collect such samples. Consequently, a light source located in the lower blade becomes obscured by blood and tissue scrapings, thus diminishing and often obliterating illumination at the very time when adequate illumination is particularly needed.
Another illuminating means has been devised and is described in U.S. Pat. No. 2,296,793, wherein a light source is wholly contained within the shell of the blade, the light being directed through a transparent closure at the tip of the blade. This arrangement has, however, proven unsatisfactory, for when the blade is inserted into the cavity the tip will become immersed in blood or tissue, thus diminishing and often completely obliterating the light. Moreover, the blade must be considerably thicker in order to accommodate the light fixture.
Other illuminated specula and retractors are shown in U.S. Pat. Nos. 726,704; 1,003,232; 1,783,602; 3,776,240; 458,708; 872,344; 339,754; 3,826,248; 471,990; 1,932,473; 648,673; and U.K. Pat. No. 25,040 of 1913. Devices of this general type have also been provided in a number of shapes, such as shown in U.S. Pat. No. 659,182.
All of these devices have, however, suffered from one or more defects; and, insofar as is known, none has ever achieved any substantial acceptance by physicians. The reason for such lack of acceptance is that none of these devices has been constructed in such a way as to provide the correct location of the light source so that the light beam therefrom will not be obscured during use of the instrument and so that the angulation of the light path permits maximum illumination of the interior of the cavity.
Providing light to the internal area of the body for surgery is an old and still unresolved problem. Most lighting mechanisms presently available, e.g. over the shoulder lamps, are not very satisfactory. Attempts by others, such as those set forth in the patents mentioned above (also there is a plastic speculum available which has a fiber optic light source on the bottom portion, but which is not effective because it does not direct light to the proper area), have not solved the problem. Many surgical procedures must be performed blindly because there is still no effective way to illuminate the interior of the body cavities.